Quoted for the truth. Guess I'm pig piling Nick's message. These cars haven't been produced in a while and springs are fatiguing. Change how far and how much something moves now that it has 100k+ miles on it.
If you choose to put higher ratio rockers on older springs, do so knowing that you stand a much better chance of breaking a spring or getting valve float than a fresh engine from the factory.
The points I always tell customers are:
1. Change in amount of movement from the norm.
2. Older fatiguing parts tend to give easier in a #1 situation
3. Liability of the motor is your choice.
4. There's more power in a cylinder with closed valves.